Connecticut MLS and the Square Footage Puzzle

I'm currently preparing a market analysis on a small (900 square feet) ranch style home in Gales Ferry. One of the first steps in doing the analysis is finding comparable active, pending and sold listings.  I searched the Connecticut MLS website for ranches in Ledyard up to 1000 square feet that were currently active or pending as well as those sold in the last 6 months.  I found a few good candidates but I knew I still had another job ahead of me.  I eliminated "1000 square feet" from the search criteria and began the arduous task of finding comparable ranches where agents had included finished basement space in their total square footage. This required me to do a case by case study of each listing in an attempt to sort out those that were around the same size as my 900 square footer.  I found several; one was listed at 1650 square feet and one was listed at 1800 square feet due to finished space in the below ground basement.  My ranch listing also had a finished room in the below ground level.

There has never been real consistency in our Multiple Listing Service for listing square footage of a ranch style home with finished space in the basement.  My rule has always been to list the main level square footage only unless the basement is a walk out and the finished space is of main level quality.  If that is the case, I'll include that finished space but make a note in the remarks section of the listing so not to fool anyone into thinking the home is larger than it is.  Unfortunately, my rule is only my rule.  My advice:  if you see a ranch home online or in the newspaper, ask the agent how many square feet are on the main level.  That's the only way you can really compare.